a) Iron III hydroxide
b) Concentrated sodium hydroxide is added at 4 atm pressure to the Bauxite at 160C AL203 dissolves in the sodium hydroxide leaving the iron III oxide as a solid
maurice.mutuku answered the question on November 1, 2019 at 08:38
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Date posted: November 1, 2019. Answers (1)
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oxygen. Write equations for the reactions...(Solved)
One of the steps in the extraction of Zinc metal from its ore is roasting of the ore in excess
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Date posted: November 1, 2019. Answers (1)
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a)Complete the table by filling...(Solved)
The following table shows some properties of period three elements and their chlorides. Study it and answer the questions that follow.
a)Complete the table by filling in the formula of the missing chlorides.
b)In terms of structure and bonding, explain the following observations:
i)The melting point of aluminium is higher than that of sodium.
ii)The melting point of chlorine is lower than that of sulphur.
iii)The melting point of aluminium chloride is lower than that of magnesium chloride.
c)Sodium chloride dissolves in water to form a neutral solution but aluminium chloride dissolves
to form an acidic solution. Explain this observation.
d)Generally, the first ionization energy increases across the period. Explain
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Date posted: November 1, 2019. Answers (1)
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Heated iron forms iron (III) chloride when reacted with chlorine and iron (II) chloride when reacted with hydrogen chloride gas. Explain this difference.
Date posted: November 1, 2019. Answers (1)
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Identify the substances with:
a)A metallic bond
b)A covalent bond
c)An ionic bond (Solved)
The table below shows some properties of substances I, J, K and L.
Identify the substances with:
a)A metallic bond
b)A covalent bond
c)An ionic bond
Date posted: November 1, 2019. Answers (1)
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a)Explain the effect of increasing temperature on the yield of nitrogen (II) oxide.
b)If 200cm3...(Solved)
Nitrogen and oxygen gases react according to the equation given below;
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Date posted: November 1, 2019. Answers (1)
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a)State and explain the difference in the...(Solved)
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b)Write an equation to show the reaction between compounds B and E and give the name of the
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Equation.
Name of product:
c)Give one chemical test that can be used to identify compound C.
Date posted: November 1, 2019. Answers (1)
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The following results were obtained.
a)Sketch the curve obtained when the...(Solved)
A series of experiments were done using 0.1g pieces of magnesium and dilute hydrochloric acid.
The following results were obtained.
a)Sketch the curve obtained when the volume of gas produced was plotted
against time for each of the experiments and label each as 1, 2 or 3.
b)Write an equation for the reaction that took place
Date posted: November 1, 2019. Answers (1)
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Explain what happens to the gaseous substance between:
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a)T and U
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a) Name:-
i) Gas Q
ii) Liquid R
(iii) Residues S
b) Name the sulphide ore used
c) Before the ore is roasted, it is first concentrated;
(i) Explain why it is necessary to concentrate the ore
(ii) Explain briefly the process of concentrating the ore
d) Write an equation for the reaction that takes place in the:-
(i) Roaster
(ii) Reaction chamber
(e) (i) Name one major impurity present in the sulphide ore used
(ii) Write an equation to show how the impurity in (e)(i) above is removed
f) Given that the sulphide ore contains only 45% Zinc sulphide by mass, calculate :
(i) The mass in grams of Zinc sulphide that would be obtained from 250kg of the ore.
(ii) The volume of Sulphur (IV) oxide that would be obtained from the mass of sulphide
ore at room temperature and pressure
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Date posted: November 1, 2019. Answers (1)
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ii)How many grams...(Solved)
A copper spoon was coated with silver metal as shown below.
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The diagram below is a flow chart for the extraction of copper. Study it and answer the questions that follow:
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(b) Name process II
(c) Give an equation for the reaction that occurs in stage III
(d) Explain what happens in stage IV
(e) Write half cell equations occurring at the anode and cathode in stage VII
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Date posted: November 1, 2019. Answers (1)
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(i) Name one major ore...(Solved)
Aluminium is the most abundant metal in the earth crust and it is widely extracted for its wide range of uses.
(i) Name one major ore of aluminium and give its formula
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Date posted: November 1, 2019. Answers (1)
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The flow chart below shows steps used in the extraction of zinc from one of its ores.
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Date posted: November 1, 2019. Answers (1)
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Date posted: November 1, 2019. Answers (1)